refactor: replace lodash helpers with native alternatives

Author: devoto13

lib/RollingFileWriteStream.js

@@ -1,5 +1,4 @@
 const debug = require("debug")("streamroller:RollingFileWriteStream");
-const _ = require("lodash");
 const async = require("async");
 const fs = require("fs-extra");
 const zlib = require("zlib");
@@ -146,7 +145,7 @@ class RollingFileWriteStream extends Writable {
       keepFileExt: false,
       alwaysIncludePattern: false
     };
-    const options = _.defaults({}, rawOptions, defaultOptions);
+    const options = Object.assign({}, defaultOptions, rawOptions);
     if (options.maxSize <= 0) {
       throw new Error(`options.maxSize (${options.maxSize}) should be > 0`);
     }
@@ -198,11 +197,13 @@ class RollingFileWriteStream extends Writable {
   _getExistingFiles(cb) {
     fs.readdir(this.fileObject.dir, (e, files) => {
       debug(`_getExistingFiles: files=${files}`);
-      const existingFileDetails = _.chain(files)
+      const existingFileDetails = (files || [])
         .map(n => this.fileNameParser(n))
-        .compact()
-        .sortBy(n => (n.timestamp ? n.timestamp : newNow().getTime()) - n.index)
-        .value();
+        .filter(n => n !== undefined && n !== null);
+
+      const getKey = n => (n.timestamp ? n.timestamp : newNow().getTime()) - n.index
+      existingFileDetails.sort((a, b) => getKey(a) - getKey(b))
+
       cb(null, existingFileDetails);
     });
   }
@@ -274,7 +275,11 @@ class RollingFileWriteStream extends Writable {
       date: this.state.currentDate,
       index: 0
     });
-    const ops = _.pick(this.options, ["flags", "encoding", "mode"]);
+    const ops = {
+      flags: this.options.flags,
+      encoding: this.options.encoding,
+      mode: this.options.mode,
+    };
     this.currentFileStream = fs.createWriteStream(filePath, ops);
     this.currentFileStream.on("error", e => {
       this.emit("error", e);
@@ -291,8 +296,7 @@ class RollingFileWriteStream extends Writable {
         this.options.numToKeep > 0 &&
         existingFileDetails.length > this.options.numToKeep
       ) {
-        const fileNamesToRemove = _.slice(
-          existingFileDetails.map(f => f.filename),
+        const fileNamesToRemove = existingFileDetails.map(f => f.filename).slice(
           0,
           existingFileDetails.length - this.options.numToKeep - 1
         );
@@ -306,7 +310,7 @@ class RollingFileWriteStream extends Writable {
   _deleteFiles(fileNames, done) {
     debug(`files to delete: ${fileNames}`);
     async.each(
-      _.map(fileNames, f => path.format({ dir: this.fileObject.dir, base: f })),
+      fileNames.map(f => path.format({ dir: this.fileObject.dir, base: f })),
       fs.unlink,
       done
     );

lib/fileNameParser.js

@@ -1,15 +1,14 @@
 const debug = require("debug")("streamroller:fileNameParser");
 const FILENAME_SEP = ".";
 const ZIP_EXT = ".gz";
-const _ = require("lodash");
 const format = require("date-format");
 
 module.exports = ({ file, keepFileExt, pattern }) => {
   // All these functions take two arguments: f, the filename, and p, the result placeholder
   // They return the filename with any matching parts removed.
   // The "zip" function, for instance, removes the ".gz" part of the filename (if present)
   const zip = (f, p) => {
-    if (_.endsWith(f, ZIP_EXT)) {
+    if (f.endsWith(ZIP_EXT)) {
       debug("it is gzipped");
       p.isCompressed = true;
       return f.slice(0, -1 * ZIP_EXT.length);
@@ -18,23 +17,23 @@ module.exports = ({ file, keepFileExt, pattern }) => {
   };
 
   const extAtEnd = f => {
-    if (_.startsWith(f, file.name) && _.endsWith(f, file.ext)) {
+    if (f.startsWith(file.name) && f.endsWith(file.ext)) {
       debug("it starts and ends with the right things");
       return f.slice(file.name.length + 1, -1 * file.ext.length);
     }
     return f;
   };
 
   const extInMiddle = f => {
-    if (_.startsWith(f, file.base)) {
+    if (f.startsWith(file.base)) {
       debug("it starts with the right things");
       return f.slice(file.base.length + 1);
     }
     return f;
   };
 
   const dateAndIndex = (f, p) => {
-    const items = _.split(f, FILENAME_SEP);
+    const items = f.split(FILENAME_SEP);
     let indexStr = items[items.length - 1];
     debug("items: ", items, ", indexStr: ", indexStr);
     let dateStr = f;

package.json

@@ -40,8 +40,7 @@
     "async": "^2.6.3",
     "date-format": "^2.1.0",
     "debug": "^4.1.1",
-    "fs-extra": "^8.1.0",
-    "lodash": "^4.17.14"
+    "fs-extra": "^8.1.0"
   },
   "engines": {
     "node": ">=8.0"